So how would you go about compensating for the drawbacks of the master summoner archetype?
I was thinking something along the lines of a Scouting/UMD/skill monkey route.
suggestions?
I think you just answered your own question. Add Disable Device if needed or wanted and you're good to go. An eidelon using wands(umd)kicks action economy in the butt. I generally use those to buff the party so as not to hog the spotlight myself.
Yep, you just answered your own question.
Treat it more as a highly customisable familiar and you're going down the right track. Eidolons can be amazingly good skillmonkeys if you build them that way.
Skilled evolution, skilled evolution, and...skilled evolution. Yep, that should cover it.
But a biped might be the best choice, since they require the least evolution points to get running (arms cost a lot). Besides that? Maybe make it small, so that it has better defense from the get go.
Armor evolutions are not bad either, just for survivability. Maybe DR if you ever find the time (it would depend on you alignment though; chaotic seems the most useful, since you only really have to worry about devils then...unless you peeve off the wrong outsiders). Some basic flight wouldn't hurt either. Fast healing is also useful, if only so you never have to waste time healing the thing.
Hmmm....looking more closely, shadow blend is rather good (you aren't hitting anything, so free miss chance is welcomed). Extra senses might be good, if you are making this into an alarm system.